The present disclosure relates generally to information handling systems, and more particularly to an Ethernet storage area network system provided with and/or utilized by information handling systems.
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Information handling systems such as, for example, switches and storage systems, are sometimes used to provide Storage Area Networks (SANs) in order to allow for the storage and retrieval of data by other information handling systems such as, for example, servers. Conventional SANs, particularly those which store and transmit sensitive data, typically employ Fibre Channel (FC) fabrics (i.e., FC switches and/or other FC networking components), and SAN administrators are typically hesitant to employ Ethernet fabrics (e.g., Ethernet switches and/or other Ethernet networking components) with their SANs despite the lower cost of those Ethernet fabrics due to several deficiencies associated with Ethernet SANs. For example, Ethernet fabrics allow devices to be connected to and unconnected from the Ethernet fabric with little to no effort to authenticate those devices or keep track of which devices are connected to the Ethernet fabric, which can be problematic for use with SANs that store and transmit sensitive information. Furthermore, the state of links between Ethernet switches in an Ethernet fabric is indeterminate and time-lagged, as there is no hardware level link state detection mechanism in Ethernet fabrics other than bit syncing and link indicators, and timeouts are typically used in Ethernet fabrics to determine link states. For example, Ethernet fabrics such as Fiber Channel over Ethernet (FCoE) use keep alive timers and run link state probes, and those techniques requires exchanges that are on the order of seconds, while utilizing retries that provide for link state awareness that lags the actual link state by 10′s of seconds and up to minutes, which causes delays in link state propagation through the Ethernet fabric and associated failover mechanisms.
Further still, Ethernet fabrics are a lossy medium where frames are delivered by best effort and can be dropped due to congestion. Flow control in Ethernet fabrics is typically accomplished by a Media Access Control (MAC) PAUSE frame, which can cause large losses of data frames when Ethernet switches get congested (as frames are discarded by the Ethernet switch cannot process them). The Ethernet Data Center Bridging (DCB) protocol standards made improvements to Ethernet fabric flow control by introducing a more granular version of the MAC PAUSE frame that provides a Priority Flow Control (PFC) mechanism between link endpoints, and adding a requirement that frames cannot just be discarded when an Ethernet switch is congested. However, as with the MAC PAUSE frames discussed above, DCB protocol standards do not provide the deterministic and controllable flow control available in FC fabrics. For these and other reasons, FC fabrics tends to be the fabrics of choice for SANs despite their higher costs.
Accordingly, it would be desirable to provide an improved Ethernet SAN fabric.